A Ni-Zn binary metal coating was electrochemically deposited on a copper electrode that was coated with nickel(bottom layer).This was then etched in concentrated alkaline solution(30 wt% NaOH) to produce a nanoporous ...A Ni-Zn binary metal coating was electrochemically deposited on a copper electrode that was coated with nickel(bottom layer).This was then etched in concentrated alkaline solution(30 wt% NaOH) to produce a nanoporous Ni electrocatalytic surface for borohydride electro-oxidation in alkaline solution.The bulk and surface compositions of the coating before and after alkaline leaching were determined by atomic absorption spectroscopy and energy dispersive X-ray analysis.The surface morphology was investigated by scanning electron microscopy.The characterization showed that the leached Ni/Zn-Ni coating has a nanoporous structure.Electrocatalytic activity for borohydride electro-oxidation was assessed by cyclic voltammetry and electrochemical impedance spectroscopy.The improved activity of the electrode was related to the removal of corrosion products and the formation of nanopores and cracks during alkaline leaching.Cyclic voltammetry studies confirmed that the alkaline leaching process improved the activity of the Ni/Zn-Ni coating in comparison to that of a smooth Ni deposit,and it gave an anodic peak current density that was 21 times higher.展开更多
An electrochemical approach to fabricate a nanostructured Fe/Pt-Fe catalyst through electrodeposition followed by galvanic replacement is presented. An Fe/Pt-Fe nanostructured electrode was prepared by deposition of F...An electrochemical approach to fabricate a nanostructured Fe/Pt-Fe catalyst through electrodeposition followed by galvanic replacement is presented. An Fe/Pt-Fe nanostructured electrode was prepared by deposition of Fe-Zn onto a Fe electrode surface, followed by replacement of the Zn by Pt at open-circuit potential in a Pt-containing alkaline solution. Scanning electron microscopy and energy-dispersive X-ray techniques reveal that the Fe/Pt-Fe electrode is porous and contains Pt. The electrocatalytic activity of the Fe/Pt-Fe electrode for oxidation of methanol was examined by cyclic voltammetry and chronoamperometry. The electrooxidation current on the Fe/Pt-Fe catalyst is much higher than that on flat Pt and smooth Fe catalysts. The onset potential and peak potential on the Fe/Pt-Fe catalyst are more negative than those on flat Pt and smooth Fe electrodes for methanol electrooxidation. All results show that this nanostructured Fe/Pt-Fe electrode is very attractive for integrated fuel cell applications in alkaline media.展开更多
基金supported by Renewable Energy Organization of Iranthe financial support of the Office of Vice Chancellor in Charge of Research of University of Tabriz
文摘A Ni-Zn binary metal coating was electrochemically deposited on a copper electrode that was coated with nickel(bottom layer).This was then etched in concentrated alkaline solution(30 wt% NaOH) to produce a nanoporous Ni electrocatalytic surface for borohydride electro-oxidation in alkaline solution.The bulk and surface compositions of the coating before and after alkaline leaching were determined by atomic absorption spectroscopy and energy dispersive X-ray analysis.The surface morphology was investigated by scanning electron microscopy.The characterization showed that the leached Ni/Zn-Ni coating has a nanoporous structure.Electrocatalytic activity for borohydride electro-oxidation was assessed by cyclic voltammetry and electrochemical impedance spectroscopy.The improved activity of the electrode was related to the removal of corrosion products and the formation of nanopores and cracks during alkaline leaching.Cyclic voltammetry studies confirmed that the alkaline leaching process improved the activity of the Ni/Zn-Ni coating in comparison to that of a smooth Ni deposit,and it gave an anodic peak current density that was 21 times higher.
基金supported by the Iranian Nanotechnology Society and the Office of the Vice-chancellor in Charge of Research at Malek-Ashtar University of Technology
文摘An electrochemical approach to fabricate a nanostructured Fe/Pt-Fe catalyst through electrodeposition followed by galvanic replacement is presented. An Fe/Pt-Fe nanostructured electrode was prepared by deposition of Fe-Zn onto a Fe electrode surface, followed by replacement of the Zn by Pt at open-circuit potential in a Pt-containing alkaline solution. Scanning electron microscopy and energy-dispersive X-ray techniques reveal that the Fe/Pt-Fe electrode is porous and contains Pt. The electrocatalytic activity of the Fe/Pt-Fe electrode for oxidation of methanol was examined by cyclic voltammetry and chronoamperometry. The electrooxidation current on the Fe/Pt-Fe catalyst is much higher than that on flat Pt and smooth Fe catalysts. The onset potential and peak potential on the Fe/Pt-Fe catalyst are more negative than those on flat Pt and smooth Fe electrodes for methanol electrooxidation. All results show that this nanostructured Fe/Pt-Fe electrode is very attractive for integrated fuel cell applications in alkaline media.
